"When Chaldea was first colonized, or at any rate when the seat of empire was first established there, the emporium of trade seems to have been at Ur of the Chaldees, which is now 150 miles from the sea, the Persian Gulf having retired nearly that distance before the sediment brought down by the Euphrates and Tigris."

Written probably when, after having repulsed the Egyptians who brought succors to the Jews (Jer 37: 5-8; 2Ki 24: 7), the Chaldees were a second time advancing against Jerusalem, but were not yet closely besieging it